The use of touch-sensitive surfaces as input devices for computers and other electronic computing devices has increased significantly in recent years. Exemplary touch-sensitive surfaces include touch pads and touch screen displays. Such surfaces are widely used to manipulate user interface objects on a display. Exemplary manipulations include adjusting the position and/or size of one or more user interface objects. Exemplary user interface objects include digital images, video, text, icons, and other graphics.
Existing methods for performing these manipulations are cumbersome, inflexible, and inefficient. For example, existing electronic devices often give little consideration to the physical orientation of a touch-sensitive surface and the relationship between the physical orientation and the characteristics of the user interface objects displayed on the touch-sensitive surface when choosing a method for manipulating multiple user interface objects on the touch-sensitive surface. As a result, an ill-chosen method may create a significant cognitive burden on a user, thereby causing the user to take longer to complete a task with the device, wasting the user's time and a device's power reserve, which can be a particularly important consideration for battery-operated devices.